Casein is a mixture of phosphoproteins naturally occurring in milk, cheese, beans and nuts. It is usually isolated from skim milk by isoelectric precipitation or by enzymatic coagulation. The isolated and recovered protein contains all of the common amino acids and is particularly rich in essential amino acids. Due to its desirable nutritional balance, casein is very useful as an ingredient in many food products such as simulated meats, cheeses and other dairy products. Unfortunately, the casein which is commercially available has the relatively high cholesterol content of between 15 and 30 mg/100 g. This high cholesterol level limits the use of casein in certain foodstuffs where a lower cholesterol level is desirable.